The present invention relates to a rocking station to be used in treatment plant conveyance systems, for example for sheet metal frameworks such as motor vehicle chassis.
In the prior art rocking stations used when it is necessary to swing objects being processed around one of the main axes to perform technological operations such as for example spraying fluids or scavenging liquids from pockets, shallow water et cetera are known.
For example in the engineering of treatment by means of fluids of the surfaces of frameworks made of sheet metal in certain steps it is necessary to change the distance and direction of fluid streams with respect to the surfaces being treated or after a typical dipping treatment in a vat or spraying it is necessary to scavenge the liquids remaining trapped in the framework by swinging it.
Usually the frameworks being processed advance while supported on a frame or base board termed xe2x80x98skidxe2x80x99 which can be provided with two sleds applied each to the framework or an actual frame in the shape of a sled on which is the framework constrained.
The rocking movement can be achieved in various ways. For example the board can be swung alternately around end axes transversal to the travel direction or the board can be swung around a central axis transversal to the travel direction.
To achieve alternate rocking around the end axes of the board various solutions, all relatively complicated, have been proposed in the prior art. For example stations powered to lift the center and two controlled bolts, one at each end, or release of one of the bolts allowing lifting of the corresponding board end have been proposed. Stations with two independent power sources, one for each board end or with a single power source equipped with an engagement and disengagement mechanism allowing alternate powering at the two ends have also been proposed.
All these solutions are relatively complicated and cumbersome and generally require relatively complicated management.
The general purpose of the present invention is to remedy the above mention ed shortcomings by making available a rocking station with simple and reliable structure, reduced space occupied and simple management.
In view of this purpose it was sought to provide in accordance with the present invention a rocking station comprising a frame in which there is a powered rocking board onto which are fed objects to be rocked characterized in that the board rests on the floor on supports arranged near its two opposite ends with the supports defining two parallel rotation axes of the board and each one near one of said opposite ends and transversal to the board with there being on each side of the board a chain defining two main lifting branches with each main branch arranged between one part of the frame above the board and couplings to the board arranged near one of said opposite ends of the board with a motor causing the chains to run on command in one or the other direction to alternately place under tension one or the other main branch and lift the corresponding board end by rotating the board around the rotation axis near the opposite end.